Sonar plugin that can detect academic code smells in Java applications
Currently only Java language is supported.
Current list of supported code smells:
| Code smell | Description |
|---|---|
| Data class | Description can be found here |
| Message chain | Description can be found here. This rule has configurable method chain length. This can be configured with property sonar.academic.plugin.message.chain.length |
| Long method | Detects methods that are longer than X lines (supports if statements, do while loops, for loops, synchronized blocks, try blocks (catch + finally), while loops). Configuratin property to configure method length is sonar.academic.plugin.long.method.length, with default value 8 |
| Switch statement | Detects usage of switch statements |
| Shotgun surgery | Detect methods that are overused by other classes |
| Lazy class | Detect classes with no methods, low complexity methods or with high coupling with other classes |
| Long parameter list | Detect methods with more than X parameters |
| Blob class | |
| Refused Bequest | |
| Comments | |
| Cyclic dependencies | |
| Tradition breaker | |
| Divergent change | |
| Feature envy | |
| Data clumps | |
| Parallel inheritance hierarchies | |
| Speculative generality (interfaces) | |
| Speculative generality (methods) | |
| Middle man | |
| Primitive obsession | |
| Brain method | |
| Inappropriate intimacy | |
| Alternate classes with different interfaces | |
| God class | |
| Intensive coupling | |
| Swiss Army Knife | |
| Missing template method | |
| Unstable dependencies | |
| SAPBreakers |
All of the examples can be found in the test resources directory of the project.
By definition, data class is something that only contains data and no other business logic methods.
So, in Java we can define data class as follows:
- A class that has only getters and/or setters
- A class that only has public variables
This narrows down the definition to the following: if class has no custom methods with any other logic that getters/setters, it is a data class code smell.
Plugin analyses a class and nested classes, and looks for getters/setters and then substracts the number of getters + setters from the total method count. If this number is zero, issue is reported to the context of the class.
By definition message chain is a delegation of method calls.
This can be described as a pattern a -> b -> c -> d etc.
Plugin analyses method invocations and measures the depth of the calls.
Investigate how many lines does the method have.
Since code follows tree-like structure, we traverse recursively into the tree and count the number of expressions in the tree recursively.
If number of expressions is larger than X we report an issue.
Find all usages of switch statements.
Report all usages of switch statements as an issue.
Detects methods of a class that are overused by external classes.
Detects classes that have either:
- 0 methods
- high number of low complexity methods
- tight coupling with external classes and deep inheritance tree
Detects all methods with more than X parameters